Class of warrant or rights issued.

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- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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Stock-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Proceeds from stock options exercised	$ 600,000		$ 564,000	$ 4,070,000
Proceeds from exercises of warrants		$ 0	$ 0	35,151,000
Number of warrants outstanding					0
Number of warrants issued			0
Chairman and CEO
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Proceeds from stock options exercised		$ 0		$ 4,100,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested stock options	2,400,000		$ 2,400,000
Weighted-average period for recognition			1 year 3 months 18 days
Aggregate intrinsic value of stock option exercised	1,900,000		$ 1,900,000
Outstanding RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period for recognition			2 years 1 month 6 days
Unrecognized compensation cost related to non-vested stock options	900,000		$ 900,000
Employee Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period for recognition			2 years 2 months 12 days
Unrecognized compensation cost related to non-vested stock options	900,000		$ 900,000
Non Employee Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period for recognition			6 months
Unrecognized compensation cost related to non-vested stock options	$ 37,100		$ 37,100